The present invention generally relates to ozone generation, and more particularly to a method and apparatus for generating ozone for eliminating pollutants from fluids and gasses.
Ozone is a powerful oxidant and disinfectant that readily oxidizes organic pollutants, inorganic pollutants, and microorganisms. Ozone is form of oxygen that has three atoms per molecule rather than the two atoms normally found in oxygen. When the extra oxygen atom splits off from the ozone molecule, one of two things happen, disinfection or oxidation. As a disinfectant, these free oxygen atoms quickly destroy bacteria and other microorganisms that they contact. As an oxidant, the free oxygen molecule reacts with existing chemical compounds and yields more benign by-products.
Ozone occurs when an electrical charge molecularly disassociates a stable molecule (O2) and splits it apart leaving two unstable atoms of oxygen. Seeking stability, these atoms attach to other oxygen molecules creating ozone (O3).
Ozone occurs naturally in the atmosphere during lightning strikes and other electric discharge phenomena. Ozone can also be artificially generated by passing air through electric discharge fields. Another method for generating ozone is passing air through ultraviolet (UV) radiation generated by UV lamps. Specifically, ozone can be formed when air or an oxygen-containing gas is exposed to ultraviolet radiation generated in the range from about 100 nanometers to about 260 nanometers.
There are several shortcomings associated with generating ozone through UV lamps. The lifetime of a UV lamp is limited due to the volatile mercury vapor used in the lamp which causes the lamp performance to deteriorate over time. Moreover, the effective ozone generating range from a UV lamp is relatively small, thereby limiting the amount of ozone that can be generated. Finally, these lamps operate at extremely high temperatures which causes the ozone to deteriorate.
Because ozone is formed by the disassociation of oxygen molecules, it is unstable and has a relatively short lifetime. Therefore, to be effective as an oxidizer and disinfectant, the ozone should be immediately inserted into the gas or fluid pollutant stream. In the case of polluted fluids, however, high temperature mercury-vapor UV lamps cannot be placed in the fluid stream because they will burst upon contact with the fluid.
Accordingly, there exists a need for an ozone generator that can generate ozone reliably without deteriorating in performance and can also be placed xe2x80x9cin situxe2x80x9d so that the ozone can be inserted into polluted fluids and gases for efficient oxidation and disinfection.
The present invention alleviates to a great extent the disadvantages of conventional ozone generating devices by providing an apparatus and method for generating ozone without using an ultraviolet mercury vapor lamp. In addition, the present invention exposes an oxygen-containing gas to the ozone generating elements at least twice, thereby increasing ozone generation.
In a preferred embodiment, the ozone generator comprises a substantially transparent tube with an inner mesh electrode arranged around an inner surface of the tube and an outer mesh electrode arranged about an outer surface of the tube. The mesh electrodes communicate with an electrical ground and an electrical power source, thereby forming a multiplicity of ozone-creating arcs that generate ozone. In one embodiment, a substantially transparent jacket encloses the tube and electrodes so that an oxygen-containing gas can be directed down the center of the tube and then redirected around the outside of the tube, thereby exposing the oxygen-containing gas to the ozone-creating arcs at least twice.
In another aspect of the invention, a housing encloses the jacket, the housing including a fluid inlet and fluid exit so that a fluid entering the housing is exposed to the ozone-creating electric arcs through the substantially transparent jacket. In another aspect of the invention, an ozone return line is coupled to the jacket and the housing so that ozone can be introduced into the fluid while the fluid is simultaneously exposed to the ozone-creating electric arcs. In this manner, a polluted fluid can be exposed simultaneously to ozone and to the ozone-creating electric arcs.
Another aspect of the present invention comprises a floatable ozone generator. The floatable ozone generator is structured to float on a fluid surface so that the volatile ozone can be produced xe2x80x9cin situxe2x80x9d and immediately introduced into the fluid, thereby maximizing the efficiency of the ozone generator. A floatable ozone generator would comprise a floatable housing containing a jacket which contains a substantially transparent tube with the tube containing an inner mesh electrode and outer mesh electrode. The inner and outer mesh electrodes communicate with an electrical ground and an electrical power source forming a multiplicity of ozone-creating electric arcs. Air or another oxygen-containing gas is introduced into the housing and thus into the jacket. As the oxygen-containing gas progresses down the jacket, it passes through and over the electrodes located on the tube thereby creating ozone. The ozone is then directed outside of the housing and into the fluid for disinfection and/or oxidation of pollutants present in the fluid.
These and other features and advantages of the present invention will be appreciated from review of the following detailed description of the invention, along with the accompanying figures in which like reference numerals refer to like parts throughout.